Electrolytic device



1942. J. B. BRENbiAN 2,290,163

ELECTROLYTIC DEVICE Filed Aug. 11, 1939 F4 4 7 i I 3 2 8 5 INVENTOR JOSEH/ .3- BIFE'IWVA/V BY I I 'ATTORNEYS' Patented July 21, 1942 ELECTROLYTIC DEVICE Joseph B. Brennan, Euclid, Ohio Application August 11, 1939', Serial No. 289,607

11 Claims.

This invention relates to electrolytic devices and more particularly to containers for electrolytic devices. The invention is described herein as applied to electrolytic condensers, but those skilled in the art will appreciate that the invention is useful in conjunction with other devices and other types of electrolytic devices such as, for example, lightning arrestors, rectifiers and the like.

It is among the objects of my invention to provide containers for electrolytic devices which will be durable and leak proof in service, and which can be manufactured and assembled at .low cost. Another object is to provide an economical method for applying a closure to such container and a further object is to provide a method of aging condensers incorporating my container construction. Another object is to provide a construction whereby an effective fiuidtight seal can be made between a thin walled metallic member and a resilient member disposed therewithin. A further object is to provide an economical method of making such a seal. Further objects and advantages of my invention will become apparent from the following description of preferred and modified forms thereof reference being made to the accompanying drawing wherein:

Figure 1 is a perspective view of a condenser made according to my invention,

Figure 2 is a view illustrating the component parts of the condenser shown in Figure 1 before the assembly has been completed,

Figure 3 is a side elevation partially in section showing the condenser of Figure 1,

Figure 4 is a side elevation partially in section of a modified form of condenser,

Figure 5 is an end elevation of the condenser I shown in Figure 4, and

Figure 6 is a somewhat diagrammatic illustration showing my aging method as applied to a condenser of the type shown in Figure 1.

It has heretofore been the practice to enclose electrolytic condensers of the paste type in containers of a cardboard which must be tarred or waxed to prevent leakage and which in spite of all precautions frequently are found to be defective. Another type of container ordinarily used in conjunction with condensers of the wet type consists of a fairly heavy gauge aluminum can having 2. depending neck portion through which the anode terminal extends. These containers are generally satisfactory but are expensive to produce and require closures at both the top and bottom thereof.

, According to my invention I eliminate the difiiculties noted above and produce a low cost yet leak proof and durable container by employing a seal or closure construction which enables me to utilize an extruded, light gauge, tube of aluminum or other ductile metal having one closed end and having the other end open for substantially the full diameter of the tube. To close the open end I employ a plug composed of resilient rubber (the term rubber as used throughout the specification and claims is intended to include not only natural rubbers and rubber-like materials, but also various synthetic rubbers and rubber-like materials) through which the condenser terminals extend. The light gauge tube does not have sufficient strength of itself to engage the plug with sufficient force to create the necessary type of seal. To obviate this difficulty, I employ a seal which is useful and advantageous in other environments, and in which the rubber is compressed into leak proof engagement with the aluminum tube by deforming the tube inwardly and clamping it into deformed position by a clamping device such as a band of wire composed of a heavier or stronger material.

Such a construction is illustrated in the drawing wherein the container, which is preferably a light gauge, extruded aluminum tube having a wall thickness of about 0.005 inch for example, is indicated at IU. In the specification and claims the terms light gauge and thin walled are used with respect to the tube or container to define a material of such thinness that it does not of itself possess sufficient strength or rigidity to engage the resilient sealing member or plug with sufficient force to create the type of seal required by the service for which the device is intended. The open end of the container is closed by a plug it of resilient rubber through which pass the terminals I2 and I d of the electrode assembly indicated generally at H3. The electrode assembly forms no part of the present invention as any ordinary type of condenser or electrolytic device may be utilized in conjunction with my container. The assembly illustrated at I? may comprise, for example, two electrodes of film forming material rolled up together with suitable spacers to prevent contact between the electrodes, the whole being impregnated with a film maintaining electrolyte which is retained within the container In.

As shown particularly in Figures 2 and 3 the component parts of a condenser embodying my invention may be assembled by merely inserting the electrode assembly l5 with the container i0, pushing the closure, member ll into the open end of the container, and slipping the ring it; over the end of the co'ntainer'in the region adjacent the plug ll. Preferably the terminals l2 and it are passed through slits cut in the plug I l before the parts are positioned in their assembled relationship. It is sometimes desirable to employ separately formed terminals [2 and I4 and weld or otherwise join them to electrode tabs or terminals I1 and I8 as indicated at 19 and 20 rather than to extend the terminals l2 and I4 into the electrode assembly. If such a construction is employed as shown in the drawing then it is preferable to position the joints id and 2b within the resilient rubber plug ii, the result being that when the plug is'compressed onto the terminals the joint is effectively sealed and protected against corrosion.

After positioning the parts as described above the ring it, which may be composed of steel or other relatively strong metal, or may be of the same material as the tube, i. e., aluminum in the present case, only of heavier gauge, is deformed inwardly. This operation may be performed by spinning or rolling the ring into the arcuate shape shown in Figures 1 and 3 thus deforming the soft ductile metal of the container ii] into intimate sealing engagement with the plug, retaining the container in sealing engagement with the plug, and compressing the plug. By reason of the compression of the material of the plug, an effective seal is made between the electrode terminals l2 and I4 and the plug, thus preventing any possible leakage of electrolyte at these points. As illustrated in the drawing the ring 5 may be provided with means for mounting the device in a support such as, for example, the perforated ears 5'2 which extend radially outwardly from the ring.

In Figures 4 and 5 I have illustrated a modified form of my invention wherein instead of the flat ring IS, a wire ring or clamp 23is employed to retain the plug Ha in the container ii). The wire may be crimped in a manner known to those skilled in the art to produce outwardly extending portions 24 thus reducing the diameter of the ring, deforming the container, compressing the plug, and firmly retaining the plug within the open end of the container In. 1

The condenser shown in Figure 4 is further modified'in the construction of the plug I la. In

' this modification the plug is composed of three layers of rubber, the two outer layers 26 and 21 being composed of harder or firmer rubber than the inner. layer 28, the three layers being vulcanized together to provide a structure in which the harder outer layers prevent buckling of the plug while the softer inner layer improves the sealing characteristics of the plug. Plugs of this sort may be produced by vulcanizing together three rubber sheets having the desired characteristics and then cutting the plugs from the sheets by means of a suitable die. Obviously the plug shown in Figures 4 and 5 may be utilized with the ring construction shown in Figures 1, 2 and 3; and similarly, the wire ring of Figures 4 and 5 may be used with the plugs of the type illustrated in Figures 1, 2 and 3.

In subjecting electrolytic condensers to their final film forming and aging process it is frequently desirable to circulate the electrolyte around and through the electrodes. This insures proper penetration of the electrolyte, and assists in dislodging gas bubbles thereby preventing defects from occurring in condensers when they are put in service. Also the temperature of the electrolyte may be maintained within the desired range. The circulation of the electrolyte maybe accomplished very conveniently with condensers embodying my invention in the manner illustrated in Figure 6. As there shown the electrodes 15, terminals l2 and I4, plugs II and ring l6 may all be assembled with the container l0. Preferably, but not necessarily, prior to deforming the ring into clamping engagement with the container, small openings as at 29 and 30 are pierced through the plug ll, preferably enco es without removing any material therefrom, and small tubes or needles 3i and 32 inserted through the openings into communication with the interior of the container iii. Electrolyte may then be pumped into the container through the tube 3!, for example, while the electrolyte flows out through the tube 32. The terminals l2 and M may be connected to a suitable source of electromotive force as by the conductors 33 and 34 and in thismanner the condenser or other electrolytic device may be subjected to the desired film forming and aging operations while electrolyte is being circulated through the condenser v by means of the tubes 3| and 32 projecting through the plug H.

After the aging process has been completed the condenser may be made ready for shipment and sale merely by removing the tubes 3| and 32 and then compressing the ring 16 inwardly to deform the container in into intimate engagement with the plug H and to compress the lug. Obviously, if the ring was compressed prior to forming the film, no further deformation will be necessary as the compressive stresses in the rubber will result in the immediate sealing of the openings as soon as the tubes are removed. The compression of the plug results in effectively sealing the openings 29 and 30 through which the tubes 3! and 32 were inserted. By this method, and with my construction the electrolyte can be circulated around the electrodes during the aging process which can be carried out with the condenser in its finally assembled form; and after the aging process has been completed the condenser can be sealed up without requiring any handling of the electrodes thus eliminating any possibility of contamination of the condenser.

In the foregoing it will be evident that I have provided a simple and economical construction for devices such as electrolytic condensers whereby light gauge metallic tubes can be utilized as containers. By my invention an effective seal can be produced between a light gauge tubular member and a resilient member disposed therewithin. Byutilizing a clamping ring such as a wire or band of stronger or heavier material than the material of the tube, the tube is reinforced at the zone where strength is needed, thus permitting the use of tubes of lighter gauge than heretofore, and making possible the production of strong and fluid tight joints with light gauge tubular members. My construction lends itself to easy and economical assembly method and condensers made according to my invention can be aged with circulating electrolytes without requiring any additional handling of the electrodes,

and in such a manner as to preclude the possibility of contamination of the electrolyte or electrode.

In-the foregoing specification I have described preferred and modified forms of my invention merely by way of example and with no intention that my patent should be limited to the precise embodiments disclosed herein. Various modifications and changes can be made in the constructions and method shown and described herein, and the invention can be adapted to other devices without departing from the spirit and scope of my invention. Therefore it is to be un-' derstood that my patent is not limited to the forms illustrated and described herein or in any manner other than by the appended claims when given the range of equivalents to which my patentmay be entitled.

I claim:

1. In an electrolytic device, a container comprising a thin walled metallic tube closed at one end and open at the other, an electrode within the container, a closure for the open end of the tube comprising aresilient rubber plug, the material of the tube being of such thinness that it does not of itself possess suflicient strength or rigidity to engage the plug with sufficient force to create an adequate seal, a terminal for said electrode passing through said rubber plug, and an endless metallic ring contracted into engagement with the exterior of said tube for clamping the material of said tube into sealing engagement with said plug.

2. In an electrolytic device, a container comprising a thin walled metallic tube closed at one end and open at the other, an electrode within the container, a closure for the open end ofthe tube comprising a resilient rubber plug, a terminal for said electrode passing through said rubber plug said terminal. comprising two pieces joined together, the joint being disposed within said plug, the material of the tube being of such thinness that it does not of itself possess sufficient strength or rigidity to engage the plug with sufiicient force to create an adequate seal, and an endless metallic ring deformed inwardly and clamping the material of said tube into sealing engagement with said plug and compressing said material against said terminal.

3. In an electrolytic device, a container comprising a thin walled aluminum tube closed at one end and open at the other, an electrode within the container, a closure for the open end of the tube comprising a resilient rubber plug, the material of the tube being of such thinness that it does not of itself possess sufflcient strength or rigidity to engage the plug with sufilcient force to create an adequate seal, a terminal for said electrodepassing through said rubber plug, and a steel ring having at least a portion thereof deformed inwardly into engagement with the exterior of said tube for clamping the material of said tube into sealing engagement with'said plug.

4. In an electrolytic device, a container comprising a thin walled metallic tube closed at one end and open at the other, an electrode within the container, a closure for the open end of the tube comprising a resilient rubber plug, thematerial of the tube being of such thinness that it does not of itself possess suflicient strength or rigidity to eng e the plug with sumcient force to create an adequate seal, a terminal for said electrode passing through said rubber plug, and a wire ring having an initial diameter substantially the same as the exterior of said tube and crimped into engagement with the exterior of said tube'for clamping the material of said tube into sealing engagement with said plug.

5. In combination, a container for electrolytic devices comprising a thin walled open ended tube of imperforate ductile material, a closure therefor comprising a resilient rubber plug, the material of the tube being of such thinness that it does not of itself possess suflicient strength or rigidity to engage the plug with sufficient force to create an adequate seal, and a clamping ring surrounding said tube and crimped into engagement therewith to contract said tub into sealing engagement with said plug.

6. In an electrolytic device a container comprising a thin walled metallic tube open at one end, a closure for the open end of the tube comprising a resilient rubber plug, the material of the 7.;

tube being of such thinness that it does not of itself possess suflicient strength or rigidity to engage the plug with sufficient force to create an adequate seal, a ring of arcuate cross section engaging the exterior of the tube for clamping the material of said tube into sealing engagement with said plug, and mounting means associated with said ring.

7. The method of making electrolytic devices which includes the steps of making an electrode and terminal assembly, passing the terminal through a resilient rubber plug, inserting the electrode into a thin walled tubular container,

the material of the container being of such thinness that it does not of itself possess sufilcient' said plug into one end of said container, positioning an endless clamping ring around said container adjacent the end thereof, and deforming said clamping ring inwardly to contract said container into sealing engagement with said plug and compress the material of said plug into sealing engagement with said terminal.

8. The method of making a fluid tight joint which includes the steps of inserting a resilient rubber member into one end of a thin walled tubular member, the material of the member being of such thinness that it does not of itself possess sufiicient strength or rigidity to engage the plug with sufficient force to create an adequate seal, positioning an endless clamping ring around said tubular member adjacent the end thereof, and deforming said clamping ring in-c wardly to contract said tubular member into sealing engagement with said rubber member.

9. The method of making electrolytic devices with said terminal, and seal said pierced opening.

10. In combination, a thin walled tubular memberof imperforate ductile material, a resilient rubber member disposed therewithin, the material of the tubular member being of such thinness that it does not of itself possess sufii- 1 comprising a resilient rubber plug, the material of the tube being of such thinness that it does not of itself possess sufllcient strength or rigidity to engage the plug with sufllcient force to create an adequate seal, and a clamping ring of arcuate cross section surrounding and engaging said tube to contract said tube into sealing engagement with said plug.

JOSEPHv B. BRENNAN. 

